1. Field of the Invention
The invention relates to a roof bolt drilling and setting apparatus connected with a displaceable mining machine in a manner relatively movable thereto and capable of being positioned outside the contour of the top view on the mining machine and of being braced between roof and floor, wherein the mining machine is equipped with a conveying means including a discharging site provided behind the travelling mechanism of the mining machine.
2. Prior Art
When driving roadways, a defined roof bolt pattern is to be observed for holding up the roof. To this end, it is known to position roof bolt drilling and setting apparatus outside the contour of the top view on a mining machine or cutting machine, wherein, in particular, if creviced roofs are to be expected, such roof bolting should be realized as close to the mine face as possible in order to keep the unsupported, or unsecured, area as short as possible. Such roof bolt drilling and setting apparatus may be connected with the cutting machine or mining machine in order to thereby safeguard the desired position near the mine face at predetermined distances relative to the mine face. Apparatus of this type are described, for instance, in Austrian Patent No. 392 119, in which the roof bolt drilling and setting apparatus are articulately connected with the cutting machine and hydraulically braceable between the roof and floor of the roadway. Another form of an articulate connection of roof bolt drilling and setting apparatus with a mining machine may be taken, for instance, from DE-A1 33 34 975. In that known configuration, the roof bolt drilling and setting apparatus are laterally connected with a mining machine via articulated arms and are braceable between roof and floor. Such an apparatus allows for parallel operation to a large extent, it being sufficient to place the respective positioning mechanism for adjusting the correct positions of the roof bolt drilling and setting apparatus out of engagement in order to ensure the free movability of the articulated arm relative to the cutting machine, wherein the roof bolt drilling and setting apparatus, after having been braced between roof and floor, remain secured in their selected positions so as to afford accordingly precise bolt holes.
However, with all of those known arrangements which basically are to ensure parallel operation, it has so far been possible to set bolt holes only outside the contour of the top view on the mining machine and, in particular, laterally outside that contour if such bolt holes were to be drilled near the mine face. In particular, with mining machines or cutting machines comprising relatively wide cutting rolls, the distances between such lateral bolt holes are, however, relatively large, thus requiring additional holes to be drilled centrally for setting what is called center roof bolts in order to hold up the roof. Such center roof bolts in hitherto known arrangements can be provided only by means of separate roof bolt drilling and setting apparatus at a large distance behind the mining machine, parallel and largely automated operation immediately following the road progress being unfeasible with the known arrangements.